Mark was a member of the 24th Mission and took refuge on the Jupiter 22 when the Resolute was attacked. When the Robinson Family managed to reactivate comm systems after crashing on the unknown planet, the first transmission they received was from Mark on Jupiter 2. ("Infestation")
Behind the scenes[]
Only Mark's voice was heard on Netflix's Lost in Space, in the episode "Infestation." He was voiced by Richard Meen.